United States Dollar is the official currency of the United States of America. Also known as the American Dollar. This is identified with its symbol ($) and with its code USD and usually abbreviated as US$. US Dollar is the money used for international transactions. Many countries use this as their official currency and for some it is de facto currency. For some British Overseas Territories make use of the US Dollar as their sole currency.
The Symbol: The symbol of the US Dollar ($) is generally written the numerical amount. It is being explained that the symbol comes from the Pillars of Hercules on the silver Spanish dollar coins that has appears as two vertical lines (||) and a cloth band wavering that forms like an S. 
The Structure: US Dollar Coin US Dollar is in form of a coin which is called as dollar coin and bill that is known as the dollar bill. Dollar coin is made up of gold, silver and base metal. There are three commonly known dollar coins. These are the Silver coin, Gold coin, and Presidential coin. The Silver coin is made of white metal issued in United States with a value of one dollar. The Gold coin or the gold-colored dollars are also produced the United States of America. The last one is the golden dollar what we call as the Presidential coin even if it is not made of gold or it doesn’t contain any element of gold it is still considered as the golden dollar because of its golden color. Moreover, the design for the obverse of the dollar coin is the portraits of presidents and it is designed by many. The reverse side has the Statue of Liberty design designed by Don Everhart US Dollar Bill The US Dollar Bill is formally divided into ten dimes. It is made of cotton fiber paper. It has a design of George Washington in obverse portion and for the reverse side it has the Great Seal of the United States.
Usage: The usage of the US Dollar is on great demand. It is being used for many countries as for trades. The US Dollar is also very useful in economy. It is also being used to show the economy status of a certain country. Generally it is used as payments mainly in travelling internationally. It is eventually used as what we call as the official dollarization. It is a process in which few nations used it as their official currency. Furthermore, it is as well as used as the set unit of currency in the international markets for supplies in gold and oil. Even the foreign companies list and sell their products in dollars. It is the proof that the US Dollar still remains as the world’s leading reserve currency. Exchange Rate For some countries a US Dollar has its different exchange rates. In countries for North and South America, Paraguay Guarani (PYG) has the biggest exchange rate of 4129.85053. And from Asia and Pacific, the biggest exchange rate for the US Dollar is the Vietnamese Dong (VND) with a rate of 20766.70826. In Europe, Belarusian Ruble (BYR) has the biggest exchange rate of 8750.02684. For Middle East and Central Asia, Iranian Rial (IRR) 10486.14037 is the largest exchange rate for the US dollar. Finally, Zambian Kwacha (ZMK) has an exchange rate of 4944.91058 and it is the biggest for Africa.